Castle season 5 is coming, which means it's time for a whole bunch of spoilers. Keep reading if you want to know a few things to expect when the show returns this fall!

Sexy Secrets

When season 4 ended with passionate kissing and a walk to the bedroom, fans had to question what could possibly come next. The Castle season 5 premiere has answers for us.First of all, we're not talking about a time jump between seasons 4 and 5. Castle executive producer Andrew Marlowe recently told TVLine some of the details:

"We're picking up the morning after, and we get to see what that looks like. We see how they both reacted to her coming over and the decisions that she's made and the situation that they now find themselves in. But as with any great moment you have in a relationship, it can't last, because real life intrudes."

Not that Castle and Beckett want that real life to come into their nascent relationship. EW.com reports that the couple will do their very best to keep everything secret. From everyone. Of course it's not going to last, but it will be a lot of fun for audiences in the meantime. "I think this year is going to be a lot about that," Castle star Stana Katic told EW.com. "The humor of two people hooking up and trying to keep it from everybody and also trying to figure it out."

Fallout from the Castle Season 4 Finale

The Castle-Beckett relationship isn't the only fallout from the season 4 finale. What else can we expect to continue as a plot in season 5?

Beckett is off the police force -- but only for now. Andrew Marlowe confirms that Beckett's resignation from her job will remain for the first episode. But that isn't a situation that's likely to last.

Captain Gates may be the reason Beckett gets her job back. "Gates is very aware of the fact that [Beckett] is a very powerful member of her police force and a valuable person to have on her team," Stana Katic told TVLine.

The immediate threat from the season 4 finale -- evil sniper Maddox (guest star Tahmoh Penikett) -- will be back. And he'll probably try to kill Beckett some more.

Supernatural and 30 Rock Actors as Guest Stars

Castle has never been a show to avoid the good guest stars, and season 5 will not end this practice. A few stars are already booked. In addition to Jack Coleman's casting as an antagonistic politician, two more guests familiar from other shows will join the upcoming season.

TVGuide.com broke the news that Chad Lindberg -- best known for his role as the computer genius, Ash, on Supernatural -- will guest-star on the second episode of Castle season 5. Lindberg will play Marco Massetti, a criminal who meets Castle and Beckett when a murder may be connected to one of Massetti's jobs.

The episode, "Secret's Safe with Me," is scheduled to run on Monday, October 1.

But the guest stars don't stop there. According to EW.com, Kevin Brown will also guest-star in "Secret's Safe with Me," The actor, familiar to comedy fans as Dot Com, a member of Tracy Jordan's entourage on 30 Rock, will play "Big" Percy Jenkins. Jenkins is an auction hunter who gets involved with a murder while bidding on storage units.

But Wait, There's More!

Haven't had enough Castle season 5 spoilers yet? Then here are a few more.

We may get to learn just a little bit more about Castle's mysterious father in season 5. Not that there are any firm plans on that yet -- Andrew Marlowe told TVLine that there was "talking" among the writers about how to approach this "delicate" subject: "We have some ideas," he said. "But we have to see how they develop out, and that's going to take us another month or so."

More certain -- and a lot more fun -- is a prospective episode of Castle planned to take place at a sci-fi convention. TVLine reports that this particular murder investigation may be filmed in a documentary style. And of course Castle will have to poke fun at star Nathan Fillion's rather extreme celebrity status at Comic-Con.